In general, wire data communication between two terminals is accomplished by using a data modem embodied in each of the terminals or by using a LAN (local area network) system. Particularly, a data modem is provided to support data-communication between personal computers. A typical personal computer is capable of supporting a variety of computer communication techniques such as serial communication using a serial port of an input/output device, parallel communication using a parallel port, LAN (local area network) communication using a LAN network system and the like.
Also wireless data communication between a plurality of pieces of computer equipment including computers, computer terminals, scanners, computer peripherals and the like, may be accomplished by a sort of radio receiver called a pager, or wireless communication modules which are positioned at both locations.
Since data communication between a computer terminal and an associated computer peripheral may be accomplished only within a cable connection range or an infrared radiation range, it cannot be accomplished if the computer terminal and the peripheral are located beyond the range of infrared radiation from each other.
Both the Harrison et al. and Freitas et al. patents, U.S. Pat. Nos. 5,068,916 and 5,321,542, respectively entitled Coordination Of Wireless Medium Among A Plurality Of Base Stations, and Control Method And Apparatus For Wireless Data Link, disclose arrangements for connecting mobile units to a base station through infrared radiation channels and then connecting the base station to other stations through a wired LAN.
The following additional patents each disclose features in common with the present invention but are not as pertinent as the references noted above.
U.S. Pat. No. 5,099,346 to Lee et al., entitled Infrared Communications Network, U.S. Pat. No. 5,469,283 to Vinel et al., entitled Optical System For connecting Customer Premises Networks To a Switching Center OF A Telecommunication Network Providing Interactive And Non-Interactive Services, U.S. Pat. No. 5,062,665 to Asako, entitled Optical Transmitting/Receiving Apparatus For Bidirectional Communication Systems, U.S. Pat. No. 5,517,608 to Suzuki et al., entitled Communication Apparatus And Method U.S. Pat. No. 5,301,353 to Borras et al., entitled Communication system And Apparatus, and U.S. Pat. No. 5,255,111 to Kwa, entitled Full-Duplex Optical Transmission System.